Chapter 6: The Amur Tiger and its Prey-Biomass
How much prey biomass must the home range of the residential tiger in Russias Far East have at least, so that it will be able to raise its cubs? That is, at the northernmost part of the range of the tiger in our time? And how large is there its home range? We shall study briefly two areas of the Amur tiger of the Siberian tiger: (a) The Sikhote-Alin Reserve, the mountain range, running north-south from about 51° to 45° North, at the Pacific Coast. And (b) the Lazovsky Reserve, south of Sikhote Alin, near Vladivostok. - Why do we want to find this out? Because some Pleistocene palaeontologists still do claim earnestly that the tiger, the cave-lion, and the woolly mammoth have lived in northern Siberia, Alaska, and the Yukon Territory during the height of the Last Ice Age, when it was much colder and dryer up there, than it is now. Some of them have at least realized now that these animals of the mammoth fauna could not have lived up there on arctic tundra, because they would have starved then to death. But now they claim: The woolly mammoth and its companions have lived in the northernmost parts of Siberia, Alaska, and the Yukon, when the land was so cold and so dry that only arctic dry steppe was able to grow up there. For details, see, please, the file: Mammoth Fauna 8: The Jarkov Mammoth.
How dense was the population of the Siberian tiger in the Sikhote Alin Reserve, up to about 51°North, when it had stabilized during the last 5 years? That, is before the Soviet Union had collapsed, when these northernmost tigers were still well protected? The following figures are from Russian research report The Amur Tiger in the USSR (1980). Much of the land is there covered by conifer-broad-leafed forests. About one third of this range the tiger does not use, because it does not contain enough prey: the alpine tundra and the spruce forests in its northern part. Every year in Sikhote-Alin, a certain number of tigresses have no young. Un-mated tigresses they have regularly observed in Sikhote-Alin Reserve (L. G. Kaplanov, 1948). This is marginal tiger habitat. That is: The tiger is living there at the northernmost part of its range. There is so little food (hoofed animals) that there are regularly tigresses, which have no young.
We should remember here: Still further north, in the Trans-Baikal Area, that is, east of Lake Baikal, in southern Siberia, tigers used to come from northern China. These tigers have often lived for years in southern Siberia. But they continued to live there only as nomads, as cats, who have no own home range. And they did not raise there any young, even when living there for many years, because there was too little food. At the Sikhote-Alin Reserve, many of the tigers are able to set up their own home range and to raise cubs, at least during some years, when there is enough food.
How large is the childbed range of the Amur tigress in Sikhote-Alin, when her cubs are still very small, when she has to suckle 1-4 small cubs? And how much prey biomass must it at least contain? This is very important, because this is the first problem, which she must solve, if she wants to be able to raise her cubs. When her cubs are still very small, she must do two things at the same time, because the male tiger, ruling her home range, does not help her at all raising her children. She must nourish then her children with her milk and protect them from enemies, from wolves, leopards, bears, and male tigers, who would kill them. But she must also leave her cave and her children and search for food: hunt hoofed animals. But she must be back again soon enough within 1 to 1 ― days -, so that she can suckle her cubs. If she stays away too long, they will starve to death, or other flesh-eaters may find them and kill them. This means: The residential tigress is only able to raise her cubs, where there are enough hoofed animals close to her den, where the ungulate prey-biomass in her child-bed range is large enough. How large?
In the Sikhote-Alin Reserve, the home range of an Amur tigress with small cubs covered 5 x 3 km or 15 kmē, according to Kaplanov, L. G. (1946). In this model I do assume: She is suckling 1-4 cubs. She needs just as much prey biomass as the non-lactating tigress in Nepal: 2950 kg live prey. This includes 30 % waste (bones and contents of the intestines), (M.E. Sunquist, 1981). But the Amur tiger does not use 20-70 % of its prey or an average 45%. That is 15% more waste. In other words: The Amur tiger uses only about 55 % of the hoofed animal, which he has killed. The remaining parts, other flesh-eaters will devour. The tigress, suckling her cubs, must eat more than the tigress, which has no cubs. I do assume here that the lactating tigress needs 27 % more food than the dry tigress. The residential tiger takes about 9 % of the total ungulate population on its home range per year. How calculated:
1 residential Amur tigress (without cubs, non-lactating) needs 2950 kg live prey per year. This includes 30 % waste (bones, intestines). At 45 % waste, she needs 3392 kg live prey per year. When suckling her children, she needs 27 % more food, than when not lactating. This adds up to 4308 kg live prey per year. The tiger takes about 9 % of the total ungulate on its home range per year. There must be then a total ungulate prey biomass of 47,867 kg on her 15-kmē home range. How much is that per square kilometre on her 15-kmē home range?
47,867 kg : 15 kmē = 3191 kg/kmē ungulate prey biomass
This means: The Amur tigress in the Sikhote-Alin Reserve needs on her 15 kmē large child-bed range a prey biomass of hoofed animals of at least 3191 kilogram per square kilometre. If it is less, her cubs will starve to death. When the cubs are larger, when able to move around, the home range of the tigress will gradually get larger.
The optimum biotope in Sikhote-Alin Reserve is 1 tigress per 250 kmē. This means: One residential tigress, raising cubs, has there a home range of 250 kmē, according to The Amur Tiger in the USSR (1980). How much ungulate biomass must her home-range then at least contain, so that she will be able to raise there two cubs? That is: what was their lean-season prey biomass: the lowest amount of food, at which this large cat is still able to live? Any surplus of food during the rest of the year is irrelevant. I do assume here: the tigress has 2 cubs. The cubs are not suckling now anymore. They are living now on meat, which their mother brings to them into their cave. They are living with their mother on her home range for 3 years. During their first year of life, the tigress and her cubs are using one third of her home range, during their second year, two thirds, and during their third year of life their whole home range of 250 kmē. They are now fully grown and do need just as much food as their mother. The ruling male tiger has three females with their home ranges. One third of his food he takes from the territory of this tigress with her two cubs. The tiger takes about 9 % of the total hoofed animal prey biomass per year from his home range.
Tigress with her small cub. From: Ronald L. Tilson et al. (eds.), Tigers of the World (1987:254).
In this model, the Amur tigress has 2 cubs in their first year of life. Her home range in the Sikhote-Alin Reserve covers 250 kmē. She is using one third of their home range, because her children are still too small. The ruling male tiger takes one third of his food from her territory.
The non-lactating tigress in Nepal, without any cubs, needs 2950 kg live prey per year. This includes 30 % waste (bones, stomach contents). But the Amur tiger does not use 20-70 %, or an average 45% of the animal, which it has killed. So she needs 3392 kg live prey per year (with 45 % waste).
The two cubs during their first year of life need 1696 kg live prey (with 45 % waste). The tigress and her two cubs during their first year of life do need then together 5088 kg live prey.
The ruling male tiger, controlling her home range, takes one third of his food from her territory: 1303 kg live prey (with 45 % waste). This adds up to 6391 kg.
The tiger takes about 9 % of the ungulate biomass per year from his home page. The total ungulate prey biomass on this home page is then 71,011 kg. How much prey biomass does this home range in Sikhote-Alin then contain, at the northernmost limit of the tigers range? The tigress is using now only 1/3 of her 250-kmē territory, or 83.3 kmē. She is not able to use now more, because her children are still too small.
71,011 kg live prey/year : 83.3 kmē = 852 kg/kmē
This means: The Amur tigress in the Sikhote-Alin Reserve, raising two weaned cubs in their first year of life, needs a prey biomass of hoofed animals of at least 852 kilogram per square kilometre. That is their lean season prey biomass. When there is less, her cubs will starve to death. Any surplus during the rest of the year is irrelevant.
Tigress with 2 cubs, 2nd year of life, Sikhote-Alin Reserve
The Amur tigress is raising now her two weaned cubs in their second year of life. They are able to move around now better and can follow her to the prey animals, which she has killed. She is using now two thirds of her 250-kmē home range: 166.7 kmē. The ruling male tiger takes one third of his food from her home range. Her home range must have then a lean season prey biomass of at least 596 kg/kmē. When there is less, her cubs will starve to death.
Tigress with 2 cubs, 3rd year of life, Sikhote-Alin Reserve
The two cubs are now in their 3rd year of life. They are now about as large as their mother. Each one of these two cubs needs now just as much food per day as their mother, if not more. They are using now the whole home range, covering 250 kmē in the Sikhote-Alin Reserve.
Their home range must have now a lean season prey biomass of hoofed animals of at least 510 kg/kmē.
When there is less, her cubs will starve to death. Any surplus during the rest of the year is irrelevant.
Siberian tigers in a zoo, in winter. From: J. Seidensticker et al.(eds.), Great Cats (1991:219)
The Lazovsky Reserve lies south of Sikhote-Alin, near Vladivostok. This is the normal habitat of the Amur tiger, with its cedars, Mongolian oaks and other broad-leafed trees of the temperate zone. There, arctic plants intermingle with plants of the sub-tropics. During the years 1974-75, in the Lazovsky Reserve, 1 Amur tigress had a home range of about 111 kmē. Further east, near the Pacific coast, the home range of one tigress covered up to 100 kmē, according to The Amur Tiger of the USSR (1980). That is, before the Soviet Union collapsed, when the Amur tiger was still well protected. How much ungulate prey biomass must these home ranges of the Amur tigress at least contain, so that this large cat will be able to live there and to raise its cubs? That is, what was their lean-season prey biomass?
Also in this model, the Amur tigress is raising two weaned cubs on her home range. They are staying with their mother three years, until fully grown. During their first year of life, the residential tigress is using only one third of her home range, since her children are still too small. They are not able to walk around yet very far. During their second year of life, the tigress is using two thirds of her home range. And during their third year of life, when her cubs are fully grown, her whole territory. Now each one of these two cubs must eat just as much as her mother. Their food contains 45 % waste. Of the slain hoofed animal, the tiger devours about 55 %. The bones, the stomach contents, and some of the meat it leaves there. This, the other large flesh-eaters will devour.
Tigress with 2 cubs in 1st year of life, Lazovsky Reserve (1974-75)
Her home range must have 71,011 kg of total prey biomass, of hoofed animals. She uses 9 % of this prey biomass per year. Her home range is 37 kmē, the part, which she is able to use, while her children are still very small. It must have then a lean-season prey biomass of at least 1919 kg/kmē. When there is less, her cubs will starve to death.
Tigress with 2 cubs in 2nd year of life, Lazovsky Reserve (1974-75)
There must be now a prey biomass of hoofed animals of 99,303 kg on her home range. She kills 9 % of this prey biomass per year. Her home range covers now 74 kmē, that is, the part, which she is able to use. How much prey biomass must it now contain, so that she will be able to live there and to raise her cubs? It contains now 99,303 kg ungulate prey biomass. 99.303 kg : 74 kmē = 1342 kg/kmē. This means, her home range must have now a lean-season prey biomass of at least 1342 kilogram per square kilometer.
Tigress with 2 cubs in 3rd year of life, Lazovsky Reserve (1974-75)
The Amur tigress is using now her whole home range, covering 111 kmē, because her to two children are now fully grown. Each one of them must eat now just as much as she does. How much ungulate prey biomass must her home range now support? - 127,544 kg : 111 kmē = 1149 kg/kmē. This means: Her home range must have now a lean season prey biomass of at least 1149 kg/kmē. Any surplus during the rest of the year is irrelevant.
Further east, near the Pacific Coast, the climate in the Lazovsky Reserve is still milder. And there is more food for the deer and wild boar, because many cedars, Mongolian oaks and other broad-leafed trees are growing there. The acorns of the oak trees and the nuts of the cedars are feeding the herds of wild hoofed animals. The tigress is using also here only one third of her home range during the first year of life of her cubs, because they are still very small and are not able to walk around yet much very far. The tiger is killing about 9 % of the total prey biomass on his home range per year. He uses only about 55 % of the total weight of the prey, which he has killed. That is, he does not use the bones and the stomach contents. Also some of the meat he will leave behind. Other predators will eat it up. The home range of the Amur tigress is here about 100 kmē large. How much ungulate prey biomass does her home range contain near the Pacific Coast?
Tigress, 2 cubs, in 1st year of life, Lazovsky Reserve (1974-75), Pacific Coast
There must be a prey biomass of hoofed animals on her home range of 71,011 kg. Of the 100-kmē of her territory, she is using now only one third, 33.3 kmē. She has now a lean season prey biomass of 2132 kg/kmē.
Tigress, 2 cubs, in 2nd year of life, Lazovsky Reserve (1974-75), Pacific Coast
Of her 100-kmē home range she is using now two thirds, 66.6 kmē. It contains now at least 99,303 kg ungulate prey biomass. It has a lean-season prey biomass of 1491 kg/kmē
Tigress, 2 cubs, in 3rd year of life, Lazovsky Reserve (1974-75), Pacific Coast
Her two cubs are now fully grown. She is using now her whole home range of 100 kmē. It contains at least 127,544 kg of ungulate prey biomass. Of this prey biomass she is using 9 % per year. Her home range supports now 1275 kg/kmē prey biomass.
The Amur tiger in Russias Far East. From: The Amur Tiger in the USSR (1980). This cat proves that neither the tiger nor the lion were able to live in northern Siberia, Alaska, and Northwest Canada during the time of the woolly mammoth in an arctic climate. They would have starved up there to death. The Amur tiger ranges now up to 51 52 North, where there are many wild boars, roe deer and red deer. The climate at the tigers present northern range limit: 1600 2000° 10°C temperature sum. The arctic tundra has only about 200° 10°C.ts. Mean annual air temperature 2 to 4^C. No permafrost. Arctic tundra 9 to 13°C mean annual air temperature, with thick, continuous permafrost.
The childbed territory of the Amur tigress, with small cubs, during the cubs first months of life, has a prey biomass of hoofed animals of 6368 to 6640 kg/kmē. The residential tiger, raising cubs, needs a prey biomass of hoofed animals of at least 3431 kg/kmē, increasing by 190 kg/kmē per year. The arctic tundra has only 18 26 kg/kmē ungulate biomass, an average 22 g/kmē. Annual increase of ungulate biomass in arctic tundra 2 kg/kmē (Hudson and Bunnel, 1980:210). The residential Amur tiger is not even found in the boreal forest (in the larch- and spruce/fir forest): there is too little food. Ungulate biomass in the boreal forest is only 200 - 500 kg/kmē.
This disproves now once of all times the out-dated belief, that the tiger, cave-lion and woolly mammoth have lived during the height of the Last Ice Age in the northernmost parts of Siberia, in Alaska and the Yukon. It disproves the assertion that these animals have lived up there on arctic tundra and dry arctic steppe, while it was so cold and dry that no trees were able to grow. They would have starved, thirsted and frozen up there to death. Neither the arctic tundra nor the dry arctic steppe are able to grow enough fodder, so that large enough herds of hoofed animals would be able to graze there. In other words, the arctic tundra and dry arctic steppe are not able to support so many hoofed animals that a residential tiger or lion, raising cubs, would be able to live up there. This also disproves quantitatively the belief that the woolly mammoth has been able to live during the height of the Last Ice Age in the Far North. That is only a pious myth, science fiction, without any scientific proof whatsoever.
When the tiger, the cave-lion and the woolly mammoth have lived in northern Siberia, Alaska, and the Yukon Territory, the climate up there had to be just as mild and as moist, as it is now in the home range of the Amur tiger, south of 51°North. No one is able to disprove this conclusion. But how was that possible? How could it have been just as warm in the Far North, as it is now at 45°-51°North? My conclusion: The tiger, the cave-lion and the woolly mammoth have lived in the Far North in a temperate climate, without an arctic winter, without ice and snow, before the global Flood of Noahs days. And they have perished up there in this global Flood, when the climate in the Polar Regions suddenly changed, when it suddenly became there very cold.